The curators of the Tate Triennial wanted to escape from the noise of modern life. What's left, says Adrian Searle, is a catalogue full of hot air and an exhibition full of lifeless art.

No artist begins from zero. They always borrow things. They copy, quote and appropriate. They steal. They also refute, exclude, displace and distance themselves from their contemporaries and from the artists of the past. Artists often imagine that there is no space left for them, and so end up turning out jokey post-constructivist ashtrays or creating visual homilies about how impossible it is to make art any more. You can make a career out of this sort of impasse. The point, however, is to go beyond it.

Which brings us to the third Tate Triennial, which opens tomorrow at Tate Britain. Beatrix Ruf, director of the Kunsthalle Zurich, has curated a no-nonsense, stripped-bare show of new British art. It feels dead. Maybe it is meant to. "This Tate Triennial," says Ruf in the catalogue, "has been configured around the themes of appropriation and repetition." In case one might think that this is a return to the postmodernist strategies of appropriation that appeared in the late 1970s and 1980s, she distinguishes appropriationist works of the new century by their eschewal of postmodernist irony, wit or caricature. The trouble is, appeals to wit, irony and caricature are just about the only ways in which much of the work here might be saved.
Ruf's introductory essay, and the contributions by various Tate curators that make up the catalogue entries on each artist, are masterpieces of institutional guff. There's no polite way of putting this: the catalogue is one of the most patronising and smug collections of redundant and frequently meaningless prose it has been my misfortune to read in a long time. Ruf and her team talk the talk: they go on about how "Cosey Fanni Tutti made a conscious attempt to locate one aspect of her artistic practice within the pornographic industry"; how Kaye Donachie "considers that painting is an appropriate medium through which to probe beliefs"; how Lucy McKenzie "maintains a hyper-awareness of the context in which art, including her own, is being made and situated"; and how, "using as his raw material such motifs as 1930s marquetry, 1970s bedspreads and pickled onions, Enrico David produces an art that is full of unresolved conflicts". None of which is of any help at all.

The Triennial starts well enough, with Rebecca Warren's amusing reinforced clay sculptures in the Duveen gallery. The weight of history, or rather of the sculptures that usually inhabit this space, is upon her. Her big-toed, huge-bummed figures always remind me of Germaine Richier on laughing gas. Rodin's kissing couple fuse into a slippery glob. She quotes Degas, Robert Crumb cartoons, Willem de Kooning's sculpted figures. Her forms slide towards the inchoate and the damaged. I wonder what might happen if Warren stopped relying on humour, which for her is always a sort of get-out clause. Later in the show's run, the rest of the Duveen will be used as a performance space, and today a Tino Sehgal performance begins, lasting for the duration of the show. I have hopes for some of these works. We need hope because right now it is in short supply.

Both Douglas Gordon and Angela Bulloch quote Duchamp. Bulloch has reworked Duchamp's Sixteen Miles of String, with which he once festooned a surrealist exhibition in New York. "I'm making a kind of hermetic artwork," she says, "and the very act of doing that is a political act in itself." Political? How? Her kilometre of string is suspended between a weird disco floor and ceiling; 1,001 numbered discs (as used in Berlin as part of a municipal tree management scheme) line the walls; there's a complex lighting system, an irritating soundtrack, various images and probably other elements I've missed altogether. I get the hermetic but where's the politics?

Gordon, meanwhile, shows a human skull that has had a star-shaped hole carved into it, remembering Man Ray's famous photo of Marcel, who once had a star-shaped tonsure shaved on to the back of his head. The skull is less gruesome than a remarkable catalogue statement by Jan Verwoert, who writes of "cutting a slice out of the substance of commodity culture to expose the structures that shape it in all their layers". The windier sort of existential book reviewers wrote similar nonsense in the 1950s.

Elsewhere in the catalogue we are told that Daria Martin's 16mm film "digs into the immaterial surface of film's projected shadow-world to add more weight, rubbing against and agitating its flatness". I have no idea what this means. Martin's film depicts hand-wringing teenage angst, a stalled ascent of the interior of the De La Warr Pavilion (Bexhill-on-Sea) in mountaineering kit, and a chorus of badly choreographed wailing women. It is like Matthew Barney's Cremaster Cycle filmed on a British budget.

Watching Luke Fowler's film, mostly using archive footage, about composer Cornelius Cardew's early 1970s Scratch Orchestra, one is unavoidably struck by Cardew's disturbing and genuine eccentricity. A previous film by Fowler focused on RD Laing. His theme seems to be the failure of idealism, and the consequences of an idea taken too far. Most artists in the Triennial either don't take ideas nearly far enough, or take them to a place where they become incomprehensible.

Mark Leckey has two works here. In one film, a camera circles the shiny reflective surface of a Jeff Koons Bunny. A second video installation, in a white carpeted room, is an animation based on Barney Farmer and Lee Healey's Viz cartoon of two drunken bakers, who carouse, puke, pass out and booze again on their endless night-shift descent into alcoholic hell. The white room is so clean, the black-and-white, animated cycle of cartoons so vomit-flecked and unpleasant, that the whole thing becomes an aversion therapy chamber, and makes you never want to eat a slice of Battenburg cake ever again. I dislike Leckey's work very much.

Cosey Fanni Tutti's archival display of top-shelf old porn, and the displays of correspondence between herself and various dim-witted porn editors in the 1970s, are not really worth reviving, unlike Marc Camille Chaimowicz's Here and There 1979-2006. This installation is based on the interior of Chaimowicz's home, replete with classic designer furniture, wallpaper and a vase of tulips. A pendulum slowly swings between the furnishings, marking time to a carousel cycle of slide projections, showing the artist at home, maundering about and staring out of the window. There's the shadow of a woman, an embrace. A quarter century on, this installation has gained a real, wistful pathos. It feels like a memento mori, a life for ever stalled.

This is one of the few works here that have an air of necessity about them. Similarly, John Stezaker's collages, on which he has worked for more than 25 years, have an authority and weight that goes far beyond their ephemeral material. The photo-portrait faces of movie stars are obscured by picture-postcard waterfalls, caves and city views. An inverted bridge becomes a smile, a face a mysterious cavern, tumbling falls and rocks resolve into a physiognomy. The mind struggles. These vertiginous images are truly fixating and disturbing. At once horrific and beautiful juxtapositions, they are also incredible manipulations - simple and masterful. They don't need all the flim-flam, and they kill almost everything else in the room.

There's too much strategic exhibition-fodder at the Triennial. And there is a lot of very bad painting. Even the one Peter Doig canvas in the show, Gasthof (2004), is not as good as an earlier, larger painting of the same subject. Both paintings depict the stage of the London Coliseum (where the painter worked as a stagehand in the 1980s), and show Doig and a friend, dressed in costume, standing before a backdrop for Igor Stravinsky's Petrouchka. The catalogue entry makes much of Doig's use of secondary source material - degraded photocopies, magazine photos, quotes from other painters. Doig's work doesn't struggle with all this. His paintings are full of irony, quotation and double quotation, memories and riffs of other painters. But they are also unmistakably themselves. No other painter here can compete. In fact, they are all terrible, or are too close to the beginning of the journey to be of more than passing interest.

Even the better artists here are served badly by this show, if only because their work is framed in an abysmal rhetoric, while the worst of them are probably absolutely thrilled to have been invited to participate. The Triennial, says Ruf, "is about finding new narratives within hegemonic codes and inventing fresh meanings within the noise of modern life". There are so many better things than this out there in the world, amid all the noise. Stuff her hegemonic codes.

· Tate Triennial is at Tate Britain, London SW1, from tomorrow until May 14. Details: 020-7887 8888; www.tate.org.uk.